Method of producing titanium



April 14,1959 A. G. FOLLQYWS ETAL METHOD 0;? PRODUCING TITANIUM FiledAug. 22, 1955.

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.5551 v V. J 2 mm N mm ww @0565 .5903; aosfiw. mw. 236cm 2%. -89; 2 35mi3a. 216:. mm no 356m 7 .5 H350 INVENTORS ALAN G. FOLLOWS PAUL A. KEENEATTORNEY INVENTORS 2 Sheets-Sheet 2 April 14, 1959 A. G. FOLLOWS ETALMETHOD OF PRODUCING TITANIUM Filed Aug. 22, 1955 $02453 .Em I

I ALAN G.FOL| OWS PAUL A. KEENE BY w ATTORNEY United States PatentMETHOD OF PRODUCING TITANIUM Alan G. Follows and Paul A. Keene,Syracuse, N.Y.,

assignors to Allied Chemical Corporation, a corporation of New YorkApplication August 22, 1955, Serial No. 529,663

13 Claims. c1.1s-s4.s

- This invention is directed to manufacture of metallic titanium.

It has been proposed to make metallic titanium by reducing titaniumtetrachloride with an alkali metal e.g. elemental sodium. Knownprocesses involve reaction at relatively low temperature of TiCl, withelemental alkali metal more or less dispersed on inert finely dividedcarrier material which may be alkali metal chloride or a portion of thereaction product of a previous cycle of operation. In the case of theuse of elemental sodium, reaction products are sodium chloride, andmetallic titanium which at this state exists in a finely divided,unstable more or less pyrophoric form. Subsequent to the reductionreaction, by procedures illustrated for example by Glasser et al. US.Patent 2,618,549 of November 18, 1952, the resulting reaction mass maybe heated or furnaced at temperatures above about 800 C. primarily toconvert the metallic titanium to a stable, ductile form which may beexposed to the air. Since this heating step is carried out attemperatures above the melting point of sodium chloride, the lattermelts, and-if desired at least some separation of sodium chloride andmetallic titanium may be obtained for example by draining some of themolten sodium chloride away from the reaction mass while the latter isundergoing heating. In this situation, at the end of the heatingoperation, the furnaced material comprises a mixture of stabilized,ductile finely divided metallic titanium and some occluded sodiumchloride. Following suitable cooling, the furnaced material, consistingof a solid, brittle mass more or less sponge-like in physical structure,may be ground and leached with water or weak hydrochloric acid todissolve out the solidified residual sodium chloride. After leaching anddrying of the resulting finely divided metallic titanium, the latter maybe arc-melted and cast in ingot form. As known in the art, metallictitanium prior to stabilization is highly reactive with even very smallamounts of elements such as oxygen and nitrogen, and therefore theentire operation up to completion of furnacing should be carried out inan inert atmosphere such as that formed by a blanket of relatively lowpositive pressure inert gas such as argon, krypton, or helium.

Heretofore, the advantages potentially possible by use of metallicalkali metal as reducing agent have not been fulfilled. A major objectof the present improvement lies in provision of processes affordingprocedures which facilitate placing the TiCl -elemental alkali metalmethod for making metallic titanium on a continuous basis. Other objectsinclude provision of processes which minimize formation of anysubstantial quantities of subquality titanium metal, and eliminatemechanical operational deficiencies, characterized by caking and ballingup of solids, and plugging of the process dispersers, reactors, heatexchangers and connecting transfer lines, to such an extentthatsatisfactory continuous operation becomes possible. Theinvention isdirected more particularly to provision of procedures for efiectingmanufacture, on a continuous basis, of reaction products consisting of2,882,144 Patented Apr. 14, 1959 ice a mixture of alkali metal chlorideand metallic titanium in the unstable form.

In accordance with one major feature of the invention,

Figure 1 is a view, partly in longitudinal section and.

partly in diagrammatic elevation of apparatus which may be employed inaccordance with the principles of the invention to effect formation ofthe metallic titaniumsodium chloride reaction product;

Fig. 2 is a diagrammatic end elevation of the apparatus of Fig. 1;

Fig. 3 is a longitudinal vertical section of one type of furnacingretort;

Fig. 4 is a longitudinal vertical section, partly diagrammatic, of amodified form of furnacing retort; and

Fig. 5 is a diagrammatic elevation of a modified form of the apparatusofFig. 1.

Referring to Fig; 1, reference numeral 10 indicates generally a,disperser-reactor comprising a horizontally elongated flat-topped,vertically-sided shell having a double U-shaped bottom 11 (Fig. 2), andsupported in the position indicated by means not shown, and closed ateither end by vertical end walls 12. Conveyor-agitator shafts 13,connected at one end to motor 14, are rotatably mounted by suitablegas-tight bearings in end walls 12. Attached to the under side of theshell top is a baffle 15 which is approximately rectangular in elevationas indicated by the dotted line 16 of Fig. 2. As shown in Fig. 1, theupper edge of bafile 15 is welded or otherwise connected in gas-tightrelation to the contiguous portion of the shell top. The bafile extendsdownwardly to approximately the circumferences of shafts 13, and ineffect partitions the shell to form in one end thereof a dispersing zone21 and in the opposite end a reaction zone 22. In the embodimentillustrated, each shaft carries a multiplicity of groups 23 of radiallydisposed conveyor-agitator paddles 24. Each group includes 4 paddles,and is axially spaced apart for adjacent groups on the same shaft, andis mounted in staggered relation with respect to adjacent groups on theother shaft. Paddles of a group are mounted in degree relation to eachother. Each paddle is adjustably attached to its shaft, and the paddlesare formed and pitched so as to move solid material through the shell inthe direction of the arrow 26, and to effect, in conjunction with rateof rotation of the shafts,

intense agitation of solids in the shell. Shafts 13 may be connected torotate in the same or opposite directions.

The shell is provided at the dispersing zone end with an inlet 29 forrecycled solids and with an inlet 30 for liquid alkali metal such aselemental sodium. TiCL, in vapor form may be introduced into the inletend of the reaction zone 22 thru a feed pipe 31 placed close to thereaction zone side of battle 15. At the discharge end, shell 11 isequipped with a hopper-like outlet 33 which feeds reaction product thrua valved connection 34 into a reactor product chamber 36. Numerals 38and 39 respectively denote sources of liquid metallic sodium, and TiClin vapor form, which materials are conducted to shell inlets 30 and 31thru suitable valve controlled pipe connections 41 and 42. Asdiagrammatically shown, particularly in Fig. 2, the interior of thereactor product chamber 36 is associated 3, with an elevatingconveyeiindicated generally by 44, which transfers reactor product tothe inlet 45 of a heat exchanger 47. Structurally, exchanger 47comprises an elongated cylindrical shell 49 having at the outlet end adischarge hopper 51-, and having rotatahly mounted in gastight relationin the end walls a shaft 54- connected to motor 55 and carrying screwconveyor flight 57 rotated and pitched to move solid material in thedirection of the arrow 58. Shell 49 is jacketed as at 59 to provide forcirculation of heat" transfer medium ordinarily needed for cooling ofsolid material being passed thru shell 49. The discharge hopper 51 ofthe heat exchanger is connected thru a valve controlled outlet conduit62 with a product receiver 64 which in turn communicates thru a valvecontrolled transfer pipe 66 with a retort charging chamber 67. A chute68 afiords means for feeding recycled solids to dispersing zone inlet29.

All of the equipment thus far described may be made of any suitablenon-corrosive and non-product contaminating material such as mild steel.Further, as previously indicated, the processes which may be carried outin such equipment are effected preferably under a relatively lowpositive pressure (e.g. 2 to 10 inches of water) of an inert gas such asargon, helium and krypton. Hence, all of the apparatus described isequipped with various inert gas supply tanks under pressure of such gas,pipe connections, gauges, etc., not shown, arranged to maintain all ofthe materials being processed, from the control valves in sodium andTiCl inlet pipes 41 and 42 thru and including the interior of retortcharging chamber 67, under the desired positive pressure of inert gas.

Fig. 3 illustrates one type of retort in which the metallictitanium-sodium chloride reactor product may be furnaced. This retort,which may be of stainless steel throughout, comprises a cylinder '70 oneend of which is closed gas-tight by disk 71. Welded to the lower end ofcylinder 70 is a flange 73 drilled to accommodate bolts 74. The bottomend of the retort comprises a similar cylinder 76 the bottom of which isclosed by a disk 77, and to the upper end of which iswelded a flange'78. Clearance and formation of contiguous faces of flanges 73 and 78are suflicient to permit, in the assembled form, clamping of screen 80between adjacent cylinder ends and the placing of an annular sealinggasket 81 between adjacent flange faces. Cylinder '70 above screen 80provides a reactor product charge compartment'83, and cylinder 76 belowscreen 80 affords a sodium chloride drain age and receiving compartment84. The furnace in which the retort of Fig. 3 may be 'placedis notshown.

Fig. 4 shows a modified type of furnacing retort 86 comprising anelongated cylinder 87, gas-tight closed at the bottom by a disk 88 andprovidedwith an integrally formedflange 89 'at the top. Adapted to reston the bottom of cylinder -87 is a second cylinde'r made in sections92am 93 in such 'a way that screen 95 may be securely clamped betweensuch sections. Section '92atfordsa reactor product charge chamber 97,and section 93provides a receiver for moltensodiurn chloride. The top ofcylinder 87 may be closed by a disk 99 provided with a valved connection101 for inertfgas. Theretort and accessories may be made ofstainlesssteel. Numeral 105 designates a furnaceshowndiagrammaticallyinto which retort 87 may be placed. I

In the modified form of 'apparatus'of Fig. 5,'structurally the disperser107 may "duplicatesubstantially the reactordis'perser of Fig. 1minus'th'e partition 15 and the TiCL; inlet 31 of Fig. 1. Thereacto'r108 of Fig. '5 may be constructed substantially the 'same as the'disperser1tl7 or Fig. except that conduit 110 provides for transfer ofthe dispersion of sodium on recycled solids from disperser 107 toreactor 108 which isjequipp'ed with'an inlet 111 for introduction ofvaporous TiCl Reactor product'lcollect'or 1-13, conveye'r system-lldfandheat exchanger 115 of Fig. 5 may be substantially the same as corresponding apparatus units of Figs. I 1 and 2.

Assuming use of elemental sodium as TiCl, reducing agent, the inventionprocess involves lowtemperature reduction of titanium tetrachloride bymeans of elemental sodium dispensed throughout a great many timesgreater weight bulk of finely divided substantially freeflowing solidcarrier material preferably consisting of a portion of the metallictitanium sodium chloride reaction product of a previous reaction cycle.More particularly, but apart from certain hereinafter describedoperation factors, principal procedural features of the presentimprovements include continuously dispersing elemental sodium in liquidform on the carrier material in a. dispersing zone in the substantialabsence of titanium tetrachloride, preferably continuously transferringthe thus dispersed elemental sodium and, carrier material from thedispersing zone into a reaction zone while continuously feeding titaniumtetrachloride in vapor form into the reaction zone to effect formationof a reaction mass comprising metallic titanium, sodium chloride andpreferably a small amount of sodium, and continuously discharging suchreaction mass from the reaction zone, it being understood that theentire foregoing operation is carried out in an inert atmosphere which,from a practical viewpoint, may be formed by a blanket of argon or othersimilar inert gas maintained under relatively low positive pressure.

Referring particularly to Fig. 1 of the drawing, practice of theinvention includes provision of a source of feasibly pure titaniumtetrachloride in vapor form, preferably held at temperature in the rangeof above the 136 C. vaporization point of TiCl to 250 C. or higher, andat pressure high enough to facilitate charging vaporous TiCL, into thereaction chamber 22 against the back pressure of the argon gas blanketmaintained therein. Operation also involves maintenance of a source ofpurified liquid rnetallic sodium. Storage tank 38 maybe arranged tosupply liquid sodium to dispersion zone inlet 30 at temperature in therange of say 110225 C. Purified metallic sodium may be obtained bymelting commercial metallic sodium, and filtering the molten materialfor example successively through 20 micron and 5 micron stainless steelfilters.

In accordance with the invention, it has been found that the followingadditional principal procedural factors and control conditionsinterdependently contribute to'the herein exemplified results:composition of the recycle, or sodium carrier, as introduced into thedispersion zone; physical nature and composition of thesodium-on-carrier dispersion, and the manner of making the same in thedispersion zone; reaction zone conditions including the carrying outof'the Na-TiCL, reaction in the presence of a certain excess of sodium;relative and total amounts of Na and TiCl fed into the process; weightratio of recycled carrier to total weight of Na and TiCl, fed into theprocess; and formation of a reaction zone exit (which includes the makeof a cycle) containing a certain amount of sodium.

The carrier of sodium or recycle used may be any relatively pure sodiumchloride, or metallic titanium permissibly theunstabilized type, or anymixture of these materials. From practical standpoint, the carrier isfinely divided substantially free fiowing'solid material which is themetallic titanium-sodium chloride reaction product resulting fromaprevious reaction cycle. 'This material, usually sufiiciently finelydivided so that passes a IOmeshscreen,mayscontain 'about 15-17% byweight of metallic titanium, although "as shown by the herein appended"examples, metallic titanium coutentis usually and preferably inthe-range "of 16-17%. "In the usual course of operations, such materialcontains small amounts of titanium-subchlorides and correspondingsmall'amounts of hereinafter more fully defined unused reactant sodium.In accordance-w ith one aspect of the-invention, the recycle, asife,dinto-the disperser,-;s l 1ould contain some hereinafter 1 more *fullydefined stoichiom'etric excess sodium, at 'least 0.l by weight,"preferably 0.2-1 :5 ,"and

most desirably 02-10%, the purpose "of which stoichiometric excesssodium content will hereinafter appear. Aside from the foregoingsubstances, the balance of the recycle material is NaCl.

A major feature constituting basis for successful continuous cyclicoperation of the present process is formation of a thorough dispersionof metallic sodium on the carrier material. Because of high chemicalactivity of sodium, in order to satisfactorily control the course ofreaction of TiCl and sodium, it is necessary to distribute only arelatively small amount of metallic sodium throughout a relatively largebody of carrier material which serves not only as a carrier for thereactant sodium reactable to produce cyclic make and other sodium notreactable to produce make, but also functions as a reaction intensityand temperature control medium which smooths out temperature conditionsin the reactor by taking up and distributing large quantities of heat.Reactant sodium is used herein to define the increment of metallicsodium which is fed into the process in amount-substantiallystoichiometrically equivalent to the total amount of introduced TiCl Inaccordance with the invention, a finish'ed dispersion as discharged fromthe dispersion zone contains not more than about 3.5%, preferably notmore than 3.0%, by weight of total metallic sodium. Minimum total Na isnot critical but is preferably 0.7% by weight. Further, it has beenfound that in order to put the TiClr-Na reaction on a successfulcontinuous basis, the dispersion of sodium throughout the carrier shouldbe effected in the substantial absence of TiCl Developmentwork showsthat if formation of the dispersion is carried out in the absence of anysignificant amount of titanium tetrachloride, it is possible to bringabout an even dispersion of sodiumgthroughout the carrier, and moreimportantly, to effect formation'of the dispersion in a dry andfree-flowing physical condition which prevents balling and plugging-upin the dispersion zone and in subsequent apparatus units.

In view of ultimate teaching herein, starting-up procedure will bewithin the skill of the art, and hence for purpose of furtherdelineation of details of the invention, it may be assumed that theprocess is under way, and that in addition to availability of vapor formTiCl and liquid metallic sodium, there is also being discharged from theheat exchanger 47 a reactor exit of a previous cycle, part of which exitis process make and, by adjustment of the valve in exchanger outletconduit 62, is transferred to product collector 64. The balance,constituting recycle of the above described composition, is passed thr-uchute 68 to the carrier material inlet 29 of the dispersing zone.

Operation effected in dispersion zone 21 is carried out at temperatureswell above the 97.6 C. melting point of elemental'sodium to insureabsence of any solid sodium during formation of the dispersion.Ordinarily, overall temperatures in the dispersion zone should be heldat not less than about 125 C., and in usual operation may lie in therange of about 140-200" C. Taking into account the size, capacity andnormal radiation heat losses of a particular piece of apparatus,temperature control in the dispersion zone may be effected by regulatingtemperatures of incoming liquid sodium or carrier material or both.Primary purpose of heat exchanger 47 is to afford supply of carriermaterial to dispersion zone inlet 29 at temperature at least above themelting point of sodium. Usually, the heat exchanger functions as acooler, but may under some circumstances be operated as a heater tobring up recycled reaction product to the required temperature prior tointroduction into the zone 21. Liquid sodium may be fed into thedispersion zone at temperature in the range of about 110-225 C., andrecycled reaction product fed thereto at temperature in the range ofabout 140200 C. It will be understood that for any given operation,temperature of incoming liquid sodium and recycle reaction product maybe adjusted with re- 6 spect to each other so asto maintain an effectiveminimum temperature in the dispersing zone.

Sodium fed into the dispersion zone thru supply pipe 41 should be suchas to provide the preferred 0.7-3.0% total sodium to recycle weightvalues noted above.

Residence time and agitation in the dispersion zone are of importance.Residence time is a factor related mostly to particular apparatus. Whilein say a ten ton metallic titanium'per day plant, residence time mayvary from 2 to 8 minutes, because of permissible variability of overalloperating conditions and of apparatus design, it is not possible tospecify residence time suitable for all operations. As previously noted,conveyeragitator design and permissible speed of rotation are such as toforward solids at the desired lineal rate while at the same timecreating violent and intense agitating conditions. Preferably, the totalvolume of material in the dispersion zone and factors of agitator paddledesign and rate of rotation are such that all during operation there ismaintained in the dispersion zone a highly disseminated body of materialoccupying the lower two thirds or more of the dispersion zone. In thecase of the particular apparatus of Fig. 1, the foregoing agitationconditions in conjunction with bafile 15 and the solids being dischargedfrom the dispersion zone under the edge of the baflle and into thereaction zone form an effective vapor seal between the reaction zone andthe dispersion zone in order to prevent the presence in the latter ofany appreciable amount of TiCl Hence, with the foregoing features inmind, for any particular design of apparatus, rate of conveyor-agitatorrotation and optimum residence time in the dispersion zone may bedetermined by test runs.

Reduction of TiCl elfected' in reaction zone 22 is exothermic. Reactiontemperature therein may lie in the range of -350 C., but is morecustomarily and preferably in the range of about -300 C. Reaction zonetemperatures below about 150 C. while useful are not conducive to bestresults. On the other hand, it is found that temperatures above about350 C. are not required, this feature of the invention affording theadvantage of use of conventionally constructed apparatus made ofrelatively inexpensive mild steel. Taking into account normal radiationheat losses from a given reaction zone, temperature control therein maybe had by regulation of variables such as the amount of reactantspresent, temperature of dispersion fed into the reaction zone, andtemperature of the TiCl vapor charged thereto. Regulation of reactionzone temperature may be had primarily by adjustment of the temperatureand to some extent quantity, of the recycled solids fed to thedisperser. Such temperature may be selected with regard to other more orless fixed operating conditions so as to maintain temperature in thereaction zone at the desired levels.

In accordance with another feature of the invention, it has been foundthat TiCl should be supplied to the reaction zone 22 in vapor form. Thisprocedure appears to promote almost instantaneous reaction andminimization of subchloride formation. More importantly, vapor formsupply of TiCL, avoids the presence of any liquid in the reaction zone,and experience indicates that this feature, in conjunction with theabove described formation of the sodium dispersion on recycled solids,is a major contributing factor with regard to avoidance of apparatusplugging and placing the process on a successful continuous operationbasis. TiCl may be fed into the reaction zone at temperatures fromslightly above the vaporization point up to 250 C. or higher if desired.

As shown by appended examples, the herein process is such that reductionof TiCl to metallic titanium approaches theoretical. Nevertheless, fromtime to time the material exiting the Na-TiCl reaction zone may containvariable relativelyvery small quantities of ti! 7 tanium sl'ubchlorides.in "these instances, the reaction zone exit also contains "nauseareactant sodium "which expression defines an increment of sodium which(a) 'Was initially Tied into the lproecs's as part of the reactantsodium and Was unused because of incomplete reduction or illicit to Ti,and (b1) exists in the reaction zone exit in amount corresponding withthe titanium subehloiiides content thereof, ie. an amount which wouldhave been used had all the 'subchlorides been fully reduced to it hasbeen found that in order *to insure the absence of titanium subchleridesin "the final metallic titanium of the process, "the material gatheredin the reactor roduct collector 64 for preferred operation ehouldcontain a small amount of stoichiometric excess sodium which ex ressiondefine's an inerernentof sodium over and above the quantity of sodiumneeded stoichiometrically to reduce all IiCl; to Ti. Thus, with res ectto material gathered in collector 64, istoichiometr ie exsodium"designates sodium "over and above any onused reactant sodium" which maybe present. a "furnaeing o eration, subsequently to be oeseribe'd,sioi'chiornetrie xcess sonium functions under the relatively rigorousfurnacin' conditions to drive to complereaction of any titaniumsubchloride's and unused "re'a'ct'ant sodium and thus clean up reductionof any subchlorides which ossibly may be present. If not needed in the-furnacing :ste to insure elimination of titanium subclilorides, thepresence of stoichiometric excess sodium afi'oriis no disadvantagesbecause of 'its ready separation -fro'm furnaced Product by a leachingto be described. 'Thus, a feature 'of the invention comprises productionof a fich -Na reaction zone "exit containing the amount ofstoichiorneltric 'eiice's's sodium desired to be present in the cyclicmake which firnay be continuously :s'epara'tetl out or the circuit andfed into bin 64. :s'toichionretrie excess sodium content of the reactionzone can "sho'uldibe at least 0. 1% by weight, may be high as about1.5%, and preferably is in the range of about 024.

Another teat-tirevindicated by ex erience to be notabl conducive to hi hreduction of Ticl obtained in the reaction zone is "n'raintenancetherein of the presence or a substantial reaction z'onc excess of sodiumover that theoretically required to completely reduce the TiCl,ipre'sent. While any substantial reaction zone sodium excess isconducive to improvement of results, it has been found that the reactionzone operation should be such {that there is constantly maintainedtherein preferably "at least about 15% by weight excess sodium over thattheoretically needed to reduce all TiCl resent to Ti. In mostoperations, such excess is well above the 15% indicated, but need not be:above about 200%. In some practice, more desirable results are obtainedwhen the "excess is not less than 'about 20%. It is :notedt'hat the"foregoing values do not include whatever relatively small uantities ofunused reactantsodium which might posi's'ibly be present, iie. broughtinto the reaction zone as a recycle constituent.

With regard to rel'ative amounts of TiCL; and "elemental sodium fed intothe process circuit through supply pipes 42 and 11, sodium is chargedtoprovide a reactant'so'cliu'm feed of at least and preferably justabout a stoichiometric quantity of reactant Na on the basis of fed 1301iie at -'all times, rio] and at least an a roximately stoi hiometricquantit bf reactant Na are bontiililu'ously fed :into the cyclicbifEllit. HGWeVe't, it will be fldfetl that the malce of each cycle isbl'ed out of' the circuit, and that the bled out make takes out of thecircuit the s'toichiorrietric excess sodium content *of such iri'ake.The 'thus lost stoichiorrretric :ence'ss sodium is referred to therein:as bleed iloss sodium? sH'enc'e, continuously or intermittently thereis aiii ttoouccit into the circuit, thrn f'stidium supply conduit '41,an additional amount or soiiiuni, over stoienitsinetrie Na requirements,approxi- Du'ring mateiy corresponding to the bleed loss sodium. inggly,it will be noted that all during o eration, yaporous TiCh is ied intothe reaction zone in {quantit which is less than that theoreticallyneeded to react with all lle mental sodium present, and also that,because of feed into the reaction zone of stoichiometric amounts of :Na:plus additional Na -equivalent to bleed loss sodium, the "abovediscussed reaction zone Na excess to-be mainiained present in thereaction zone always may be held constant at a chosen level, i.e.preferably not below the indicated by weight.

The total weight'of TiCl and "of reactant Na (which does not include thesmall amount of bleed losssodium preferably used to 'olfset Na loss inthe make) '-fed into the circuit may be varied depending upon thequantity of carrier material recycled. A further feature of theinvention comprises regulating the amount of recycle charged into 'thedispersion zone so as to provide in the reaction zone a preferred weightratio of recycle to total weight of (a) fed TiCl; :plus (1)) anapproximately stoichiom'etric equivalent of fed reactant Na, preferablyapproximately in "the range of 60:1 to 1. Previous discussion shows that*for best operation im ortant neocess factors are :1) a dispersion zoneexit containing not more than 3.5% by weight of total Na, preferably notmore than 3%; ('2) maintenance :in the reaction zon'e'of the presence ofpreferably at least :a 15% excess or We over that needed totheoretically react with all thelliGl; present; 3) and for'rnation of areaction zone exit con taining stoiohiorn'etric 'eirce'ss sodium inamount preferabry in the ra'nge of about 012 1 .0% by weight. Inoordanee with the invention, it has been :iound that wh'en Tich and theapproximately stoichiornetric quantityot reactant .Naare ted into the'eircuit thru conduits 42 and 41, and the recycle employed containsabout 01 13097, by Weight of stoiehiometrie excess Na, if the preferredweight ratio :ra-nge of :1 to :1 is utilized, operation is such that thethree just previously named pr'oces's factors are automaticallyrnaintained.

"when, as preferred, the recycle employed contains o. 2-1.;0% bywei h'tof -stoichiometric eiicess Na, the 25: 1 weight r'atio' providesdisperser zone exits containing about h s-253% by "weight "of Na;ihe'presen'ce in the reaction zone ofa 15-75% by weight reacti'on zoneexcess of Na over that needed to react theoreticallywith all of the TiCl'fe'd (which reaction zone excess does not include whatever'amo'unt ofNa ma'y he introduced into the *c'ir- "cuit to offset bleed losssodium); and reaction zone eiiits containing about on-1.0% by weight ofstoichionrethie 'ei'ices's Na. On the 'otherhand, the 60:1 weight ratioprovides dispersion zone exits containing about 0.7 1535 by Weight ofNa; the presence in the reaction zone "of about 36 18096 b weight-excessof Naover that needed to react theoretically with all the Ticl fed; andreaction zone exits containing about 0.2-1.()% by weight "of'stoichioni'e'tric excess Na. when desired to insure "the presence inthe reaction "zone of a greater minimum excess "of sodium, o erationsmay beconoucted so "that the described "Weight ratio is in the range of"about 605 1 "to 33:1. When using the 3321 ratio and the preferred0.'2-l;'0'-% by weight 'st'oichiometric excess N'a recycle,disperser'zone "exits may 'contain'about '1.2'2;0% -Na;"t h'e sodiumexcess in the reaction zone is in the range of about maroon, and reactiovzone exits contain about 032 1 KW, -o"tstoichiotnetrieesrcess Na. Bywayor illustration, when e loying apparatus similar to that show in Fi s.'1 and 5 of "the drawing, assuming about 1'0 tons "per day production ofmetallic titanium, substantiall all heat removal from the "system by"means or h'ea't "exchanger -47, a :dispe'r'sion "zone exit temperatureof about 1*2'5 and "use of a recycle containing about '0I2% by weight orstoichiometir excess Na-"when wonking with a ratio iii-3 the dispersionzone exit eontoins by Weight about 1.2% Na, ihe'react'ion :zonesodium-ek to "Cc'ss pre'seiit'ih' t'he reaction zone about "20%byweight,

the reaction zone exit containsabout 0.2% by weight of stoichiometricexcess Na, and the reaction zone temperature sustains itself at about250 C. or something a few degrees less. Herein given values as to Nacontent of dispersion zone exits do not include the whatever relativelysmall quantities of unused reactant Na which might possibly be present,i.e. brought into the disperser as a recycle constituent.

Agitation and residence time conditions in the reaction zone aregenerally comparable with those described in connection with thedispersing zone. Although in the reaction zone thorough agitation isequally important, residence time is not so much so since reaction forthe most part appears to be instantaneous. Thus, residence time in thereaction zone approximately the same as that in the dispersion zone,while not necessary, beneficially promotes completion of reaction. Sincevolume of solids in the reaction zone increases in accordance with themake of any incremental portion of a reaction operation, the reactionzone solids volume runs higher than that of the dispersion zone.Accordingly, if desired, the paddles of the conveyer-agitator in thereaction zone may be more steeply pitched to effect more rapid passageof solids thru the reaction zone, this procedure being possible becauseresidence time in the reaction zone may be appreciably less than optimumresidence time in the dispersing zone.

By means of reactor exit product collecting and elevating apparatusindicated in Fig. 2, reactor product recovered in chamber 36, ordinarilyat temperature not much below the average temperature level existing inthe reaction zone, may be introduced continuously into heat exchanger 47via inlet 45. Under practically all good operating conditions, thereactor exit as fed into the heat exchanger is at temperature above thetemperature desired for recycled solids in chute 68 connected todispersing zone inlet 29. Rate of flow of cooling medium, such as asuitable oil, thru heat exchanger jacket 59, and rate of movement ofreactor product thru the heat exchanger are regulated primarily tofacilitate feeding into chute 68, at the proper temperature, thatportion of reactor product to. be recycled. The remainder of materialdischarged from the heat exchanger, corresponding to the process make,is transferred thru pipe 62 into the reactor product collecting bin 64.As previously described, this material is dry, free-flowing and usuallycontains by weight about 16-17 titanium in the unstable form, smallcorresponding amounts of titanium subchlorides and unused reactantsodium, balance being NaCl plus preferably 02-10% of stoichiometricexcess Na. The foregoing product, still blanketed by positive pressureargon, is then heat-treated at higher temperatures to convert theunstable metallic titanium to the stable, ductile form. Heat treatmentmay be efiected in a retort such as shown in Fig. 3.

The retort is dismantled (bolts 74 removed) and placed in a retortcharging chamber indicated at 67. The chamber, communicating feed pipeand retort are air-evacuated and blanketed with positive pressure argon.The long end 70 of the retort is charged with solids from the reactorproduct storage bin 64 by transfer thru conduit 66. The reactor isassembled with filter screen 80 and gasket 81 in place, the retort endsare bolted together, and the unit is removed from the argon atmosphereof the charging chamber to the air. The filter element 80 may be 0.04inch wire cloth made of stainless steel. It will be understood that thesolid material in the retort at this stage is still under the positiveargon pressure existing in the charging chamber.

With the short end 76 of the retort down, the retort may be lowered intoa gas-fired furnace (not shown) in which the material in the tube isheated for a substantial time at temperatures above the 804 C. meltingpoint of sodium chloride and below the temperature at which metallictitanium begins to alloy with iron, i.e.

10 about 975 C. More particularly, heating may be efiected attemperature in the range of about 850 to 950 C. for from 2 to 4 hours.During heating, sodium chloride melts, and the metallic titanium isconverted to the stable form. More or less sodium chloride drains thrufilter 80 and collects in lower retort chamber 84. In the course offurnacing, solids in the upper end of the retort shrink away from theside walls thereof, and on completion of heating the solid residue incompartment 83 is more or less rod-like in form approximated by thedotted line 82 shown in Fig. 3. r

The tube is removed from the furnace, cooled and opened. The shrunk rod,easily shaken loose from the filter wire 80 and from any incidentalpoints of contact with the lower periphery of the tube 70, is afrangible, more or less sponge-like mass which in a typical operation aspresently illustrated may contain by weight about equal parts ofmetallic titanium and solidified NaCl. This material is crushed to below$4 inch, leached with about a 3% HCl solution, and then with water untilchloridefree. The solid residue may be methyl alcohol washed and driedat about 60 C. in vacuum. The dried material is stabilized, ductilemetallic titanium, i.e. so-called sponge, all of which passes about a 6mesh screen. If desired, the product may be arc-melted and cast intoingots.

Furnacing of reactor product in the apparatus of Fig. 4 is approximatelythe same as in the retort of Fig. 3. Re tort 86 is charged in retortcharging chamber 67, and then transferred to furnace 105, after whichthe interior of retort 86 is kept under argon blanket by connecting anargon source to pipe 101 and opening the valve thereof.- Subsequentoperation may be substantially the same as noted in connection with theretort of Fig. 3.

Taking into consideration the 623 C. melting point of K, the 776 'C.melting point of KCl, the 5 C. melting point of the equimolecular NaKalloy, and the approxi" mately 660" C. melting point of theequimolecular =NaC1--KC1 mixture, it is within the skill of the art touse potassium or the NaK alloy in place of sodium in practice of theinvention.

The following examples illustrate practice of the in vention.

Example 1.This operation was carried out in appa ratus substantially thesame as illustrated in Figs. 1 and 3 of the drawing. Internal axiallength of the reactor disperser unit 10 was about 72 inches, internalvertical cross-sectional area about 1.25 sq. ft., and bafiie 15 waslocated about midway of the unit. The unit was wrapped in a 1.5 inchlayer of insulating material to reduce radi ation losses. The interiorofthe entire apparatus thru and including the reactor product storagebin 64 was maintained all during operation at a positive pressure ofargon of about 2 inches of water.

The following delineates average conditions over an approximately 3 daycontinuous run.

Reactor product from previous cycle, analyzing byweight about 0.5%stoichiometric excess Na, and with balance about 16.9% Ti and 82.6% NaCl(basis complete reduction of TiCl to metallic Ti), was continuously fedthru chute 68 into disperser inlet 29 at temperature of a few degreesbelow C. and at the rate of about 840 lbs./hr. Commercial metallicsodium was melted and purified by filtration successively thru 20 and 5micron stainless steel filters. Purified liquid sodium (reactant sodium)was introduced into disperser inlet 30 thru conduit 41 at temperature ofabout C. and at a rate ofabout 5 lbs./hr. The combined quantity ofrecycled solids and sodium fed provided about 40 lbs. of material in thedispersing zone during operation. Average temperature in the dispersingzone was of the order of 140-l60 C. Pitch of the conveyer paddles andthe approximate 200 r.p.m. rotation of the conveyer shafts 13, rotatingin the opposite directions (arrows 17,'Fig. 2), maintained conditions ofvigorous agitation and: tumbling of material such that the dispersionzone was.

flooded to a. level above the under edge of balfie 15 and providedresidence time of incremental portions of the dispersion in thedispersion zone of about 3 minutes. Including the stoichiometric excesssodium contained in the recycled solids as fed into the dispersing zone,the Na content of the dispersion, as continuously discharged in afree-flowing condition into the reaction zone thru the relativelyvapor-tight seal formed under the edge of bafile 15, was about 1.1% byweight.

Vaporized TiCl at temperature of above 140 C. was fed continuously intoreaction zone inlet 31 thru inlet pipe 42 at rate of about lbs./hr.,i.e. substantially the amount of TiCl theoretically needed to react withthe reactant sodium fed in thru disperser inlet 30. The total quantityof TiCl introduced was such that, including the stoichiometric excesssodium content of the recycle and the reactant sodium fed into dispersedinlet 30, there was present in thereaction zone about 4.2 lbs/hr. of Nain excess of that theoretically required to react with all the TiCL;charged, that is, the reaction as a whole was continuously carried outin the presence of not less than about an 84% by weight excess of sodiumover theory. Exothermic reaction took place, and reaction zonetemperature was within the range of about 200 to 230 C. Residence timeand conditions of highly vigorous agitation of solids in the reactionzone were about the same as in the dispersion zone. Reactor product,which included make and recycled solids, was continuously dischargedinto reactor product receiver 36 at rate of about 855 lbs/hr. attemperature of approximately 220 C.

Such product was continuously fed into inlet 45 of heat exchanger 47 ata temperature of about 170 C. Heat transfer medium employed wasconventional high temperature heat transfer oil. The particular heatexchanger employed was jacketed and equipped with a screw conveyerprovided with means for circulation of cooling medium therethru. Inlettemperature and How of cooling medium thru the jacket and thru theconveyer, and rate of rotation of the conveyer were such that solidswere discharged continuously into heat exchanger outlet 51 attemperature of about 145 C. By suitable adjustment of the valve intransfer conduit 62, about 840 lbs/hr. of solids were returned to thedispersing zone, the balance, constituting approximately the make, wasrun into reactor product collecting bin 64 at the rate of about lbs/hr.This product analyzed by weight 0.5% stoichiometric excess sodium, andwith balance about 16.9% Ti and 82.6% NaCl (basis complete re duction ofTiCl to metallic Ti). Weight ratio of recycle to the total weight of fedTiCL, and fed reactant Na in this operation was about 56/ 1. During thecourse of the run, there was added a small but sufiicient additionalamount of sodium above overall theoretical requirements to offset thebleed loss sodium corresponding to the amount of stoichiometric excesssodium discharged into product collector bin 64 as a constituent of themake. In this manner, the presence of the above-noted 84% excess ofsodium in the reaction zone 22 was maintained throughout the operation.The foregoing run was continuous without interruption, and no balling upof material or plugging of any of the apparatus was encountered.

A 5-6 pound sample of product collected in bin 64 was placed in aretortsimilar to that of Fig. 3 in the argon blanketed manner alreadydescribed. The retort and the material contained therein were placed ina gasfired furnace and heated therein at temperature in the range ofabout 850. to 950 C. for a period of about 4 hours. The retort wasremoved from the furnace. cooled, opened to the. air, and the solidresidue was found to be" substantially all. shrunk away from the retortwalls and-to be. in the formapproximately as indicated by the dottedline 82 in-Fig; 3. The mass was easily shaken loose from screen 80 andthe lower periphery of retort section 70. Color was relatively lightgrey, and physical structure was cellular and more or less sponge-like.The quantity of sodium chloride which drained into retort bottom section76 during furnacing was such that the solid residue recovered fromretort section 70 contained about 50% by weight of metallic titanium andabout 50% by weight of NaCl.

The foregoing material was crushed to pass 6 mesh, leached 3 times witha 3% HCl solution, and then waterwashed about 4 times until filtrate waschloride-free. The water-washed material was then Washed once withmethyl alcohol and once with ether, and dried at about 60 C. in vacuum.Notwithstanding some known air leakage into the retort during furnacing,the dried ma terial analyzed by weight not less than 99.5% Ti, andcontained not more than 0.25% oxygen, 0.25% nitrogen, and 0.05% carbon.A sample of this sponge product was arc-melted under an argon blanket,and the resulting ingot had a Brinell hardness of 220.

Example 2.-This operation was carried out in apparatus substantially thesame as illustrated in Figs. 5 and 4 of the drawing. Internal axiallength of each of the disperser 107 and of the reactor 108 was about 72inches, and internal vertical cross-sectional area of each about 1.25sq. ft. Both units were wrapped in a 1.5 inch layer of insulatingmaterial to reduce radiation losses. The interior of the entireapparatus of Fig. 5 thru and including the reactor product storage bin120 was maintained all during operation at a positive pressure of argonof about 9 inches of water.

The following delineates average conditions over an approximatelytwo-week continuous run.

Reactor product from previous cycle, analyzing by weight about 1.0%stoichiometric excess Na, with balance about 16.8% Ti and 82.2% NaCl(basis complete reduction of TiCL; to metallic Ti), was continuously fedthru chute 117 into the inlet of disperser 107 at temperature of a fewdegrees below 170 C. and at the rate of about 1500 lbs/hr. Commercialmetallic sodium was melted and purified by filtration successively thru20 and 5 micron filters. Purified liquid sodium (reactant sodium) wasintroduced into the inlet of the disperser thru conduit 121 attemperature of about 180200 C. and at a rate of about 10 lbs./hr. Thecombined quantity of recycled solids and sodium fed provided about lbs.of material in the disperser all during operation. Average temperaturein the disperser zone was about 165 C. Pitch of the conveyer paddles andthe approximate 168 r.p.m. rotation of the conveyer shafts 13, rotatingin opposite directions as in Example 1, maintained conditions ofvigorous agitation and tumbling of material such that the dispersionzone was flooded above the level of shafts 13 and provided residencetime of incremental portions of the dispersion in the disperser 107 ofabout 3 minutes. including the stoichiometric excess sodium contained inthe recycled solids as fed into the disperser, the Na content of thedispersion, as continuously discharged in a freefiowing condition intotransfer pipe was about 1.7% by weight. The relatively smallcross-section of conduit 1.10 and the downflow of solids into reactor108 formed a seal which prevented the presence of any significant amountof TiCl in the disperser 107.

Vaporized TiCl at temperature of about 220 C. Was fed continuously intothe reactor 108 thru inlet pipe 111 at rate of about 20 lbs./hr., i.e.substantially the amount of TiCL; theoretically needed to react with thereactant sodium fed into disperser inlet 30. The total quantity of TiCL,introduced was such that, including the stoichiometric excess sodiumcontent of the recycle and the reactant sodium fed into disperser inlet121, in the reactor there was present about 15 lbs/hr. of Na in excessof that theoretically required to react with all the TiCl charged, thatis, the reaction as a whole was carried out continuously in the presenceof not less than about a by weight excess of sodium over theory.Exothermic rea tion took place,- and reaction zone temperature waswithin the range of 200 to 250 C. Residence time and conditions ofhighly vigorous agitation of solids in the reaction zone were about thesame as in the disperser. Reactor product, which included make andrecycled solids, was continuously discharged into reactor productreceiver 113 at rate of about 1530 lbs/hr. and at temperature of about225 C.

Such product was continuously fed into inlet 123 of heat exchanger 115at a temperature of about 185 C. Heat transfer medium employed wasconventional high temperature heat transfer oil. As in Example 1, theheat exchanger was jacketed and equipped with a screw conveyer providedwith means for circulation of cooling medium therethru. Inlettemperature and flow of cooling medium thru the jacket and thru theconveyer, and rate of rotation of the conveyer were such that solidswere discharged continuously into heat exchanger outlet pipe 125 attemperature of about 170 C. By suitable adjustmentof the valve intransfer conduit 125, about 1500 lbs./ hr. of solids were returned thruchute 117 to the disperser, the balance, constituting approximately themake, was run into reactor product collecting bin 120 at the rate ofabout 30 lbs./hr. This product analyzed by weight about 1.0%stoichiometric excess Na, with balance about 16.8% Ti and 82.2% NaCl(basis complete reduction of TiCl to metallic Ti). Weight ratio ofrecycle to total weight of fed T iCl and fed reactant Na was about 50/1.During the course of the run, there was added a relatively small butsufiicient additional amount of sodium above overall theoreticalrequirements to offset bleed loss sodium corresponding to the amount ofstoichiometric excess sodium discharged into product collector bin 120as a constituent of the make. By such procedure, the presence of theabove noted 150% excess of sodium in the reaction zone 108 wasmaintained throughout the operation. The foregoing run was continuouswithout interruption, and no balling up of material or plugging of anyof the apparatus occurred.

A 3 pound sample of product collected in bin 120 was placed in a retortsimilar to that of Fig. 4 in the argon blanketed manner alreadydescribed. The retort and the material contained therein were placed ina gas-fired furnace and heated therein at temperature in the range ofabout 850 to 950 C. for a period of about 4 hours. The retort wasremoved from the furnace, cooled, opened to the air, and the solidresidue was found to be substantially all shrunk away from the walls ofcompartment 97 and to be in the form approximately as indicated by thedotted line 82in Fig. 3. The mass was easily shaken loose from screen 95and the lower periphery of retort section 92. Color was relatively lightgrey, and physical structure was cellular and more or less sponge-like.The quantity of sodium chloride which drained into retort bottom section93 during furnacing was such that the solid residue recovered fromretort chamber 97 contained about 50% by weight of metallic titanium andabout 5 0% by weight of NaCl.

The'foregoing material was crushed to pass 6 mesh, leached 3 times witha 3% I-ICl solution, and then waterwashed about 4 times until filtratewas chloride-free. The water-washed material was then washed once withmethyl .alcohol and once with ether, and dried at about 60 C. in

vacuum. The dried material analyzed by weight not less than 99.5% Ti,and contained not more than 0.2% oxygen,w0.05% nitrogen, and 0.05%carbon. Samples of this sponge product were arc-melted under an argonblanket, and the'resulting ingots had a Brinell hardness in the range-of141-157, averaging 150.

Example 3.Operation was continued under substantially the sameconditions as given in Example 2, and at the end of about another week,a sample of make" was processed-as described to sponge which wasconverted to ingot form having a Brinell hardness of 134 and contained0.036% nitrogen.

We claim:

process for making metallic Ti involving a circuit comprising adispersing zone for dispersing Na on solid finely divided carrierreaction product of a previous cycle, a separate reaction zone forreacting Na and TiCl to form metallic Ti, a recycle of carrier reactionproduct thru said zones in the order named, and separation from thecircuit of reaction product formed during a cycle, the steps comprisingproviding a recycle carrier consisting of reaction product of a previouscycle and containing metallic Ti, NaCl and about 0.2-1.0% by weight ofstoichiometric excess Na, introducing said carrier into said dispersionzone, feeding elemental Na in liquid form into said zone and dispersingthe fed Na on said carrier while at temperature high enough to insureabsence of solid sodium but not higher than about 200 C. and while inthe absence of TiCl transferring the thus dispersed Na and carrierthereof into said reaction zone, feeding TiCl in vapor form into saidreaction zone while in the absence of sodium from source other than saiddispersing zone and maintained at temperature in the range of about 300C. to effect formation of metallic Ti and NaCl from fed reactants,regulating relative amounts of Na and TiCl charged to provide a Na feedof about a stoichiometric quantity of Na on the basis of fed TiCL, plusa Na excess approximately corresponding to the amount of bleed loss Nacontained in hereinafter separated cyclic make, regulating the amount ofrecycle charged into the dispersion zone so as to provide in thereaction zone a weight ratio of recycle to total weight of fed TiCl plusan approximately stoichiometric equivalent of fed Na substantially inthe range of 60:1 to 33:1, discharging reaction mass from the reactionzone, separating from said mass reaction product in amount correspondingapproximately to cyclic make, and recycling substantially the balance ofsaid mass to the dispersion zone, the entire foregoing operation beingcarried out in an inert atmosphere.

2. In a multi-stage process for making metallic titanium involving lowtemperature reduction of titanium tetrachloride with elemental alkalimetal, of the group consisting of sodium, potassium and NaK alloy,dispersed throughout a many times greater Weight bulk of finely dividedsubstantially free-flowing solid carrier material of the groupconsisting of alkali metal chloride, metallic titanium and mixturesthereof, the improvement comprising dispersing elemental alkali metal inliquid form on the carrier material in a dispersing zone while held attemperature such as to maintain alkali metal in liquid form and highenough to insure absence of solid alkali metal and while maintaining theabsence of titanium tetrachloride, thereafter transferring the thusdispersed elemental alkali metal and carrier material thereof from saiddispersing zone into a separate reaction zone while in the absence ofalkali metal from source other than said dispersing zone and Whilefeeding titanium tetrachloride in vapor form into said reaction zone andwhile maintaining therein moderately elevated temperature substantiallybelow the fusion point of the chloride of the reducing alkali metal buthigh enough to effect production of a reaction mass comprising metallictitanium and alkali metal chloride, and discharging said reaction massfrom said reaction zone, the entire foregoing operation being carnamed,and separation from the circuit of reaction prod-- uct formed during acycle, the steps comprising providing a recycle carrier. conslsting ofreaction product of a previous cycle and containing metallic Ti andalkali metal chloride, introducing said carrier into said dispersionzone, feeding into said dispersion zone liquid elemental alkali metal,of the group consisting of Na, K and NaK alloy, the amount of metalbeing restricted so as to provide in the dispersion Zone a many timesgreater weight bulk of carrier, passing thru said dispersion zone saidalkali metal and said carrier while held at temperature such as tomaintain alkali metal in liquid form and high enough to insure theabsence of solid alkali metal, and while in the absence of TiCL, andwhile under conditions of residence and vigorous agitation bothsufficient to effect dispersion of said metal on said carrier,thereafter discharging the mass of thus-dispersed elemental metal andcarrier from said dispersing zone and introducing said mass into saidseparate reaction zone, feeding into said reaction zone vaporous TiCl inquantity less than that theoretically needed to react with all theelemental alkali metal present, maintaining in said reaction zonemoderately elevated temperature high enough to effect reduction of TiClto metallic titanium and substantially below the fusion point of thechloride of the reducing alkali metal, passing the reactants thru saidreaction zone while in the absence of alkali metal from source otherthan said dispersing zone and While under conditions of temperature,residence and vigorous agitation all sufiicient to elfect formation of areaction mass comprising metallic Ti, alkali metal chloride andelemental alkali metal, discharging said reaction mass from the reactionzone, separating from said mass reaction product in amount correspondingsubstantially to cyclic make, and recycling substantially the balance ofsaid mass to the dispersion zone, the entire foregoing operation beingcarried out in an inert atmosphere.

4. In a substantially continuous multistage cyclic process for makingmetallic Ti involving a circuit comprising a dispersing zone fordispersing alkali metal on solid finely divided carrier reaction productof a previous cycle, a separate reaction zone for reacting alkali metaland TiCl to form metallic Ti, a recycle of carrier reaction product thrusaid zones in the order named, and separation from the circuit ofreaction product formed during a cycle, the steps comprising providing arecycle carrier consisting of reaction product of a previous cycle andcontaining metallic Ti and alkali metal chloride, introducing saidcarrier into said dispersion zone, feeding into said dispersion zoneliquid elemental alkali metal, of the group consisting of Na, K and NaKalloy, the amount of metal being not substantially in excess of 3.5% byweight of total fed metal and carrier, passing thru said dispersion zonesaid alkali metal and said carrier while maintained at temperature nothigher than about 200 C. but high enough to insure the abence of solidalkali metal, and while in the absence of TiCL, and while underconditions of residence and vigorous agitation both suflicient to effectdispersion of said metal on said carrier, thereafter discharging themass of thus-dispersed elemental metal and carrier from said dispersingzone and introducing saidmass into said separate reaction zone, feedinginto said reaction zone vaporous TiCl in quantity less than thattheoretically needed to react with all the elemental alkali metalpresent, maintaining temperature in said reaction zone in the range ofabout 150-350 C., passing the reactants thru said reaction zone while inthe absence of alkali metal from source other than said dispersing zoneand while under conditions of residence and vigorous agitation bothsuificient to effect formation of a reaction mass comprising metallicTi, alkali metal chloride and elemental alkali metal, discharging saidreaction mass from the reaction zone, separating from said mass reactionproduct in amount corresponding substantially to cyclic make, andrecycling substantially the balance of said mass to the dispersion zone,the entire foregoing operation being carried out in an inert atmosphere.

5; Ina substantially continuous multistage cyclic process for makingmetallic Ti involving a circuit comprising a dispersing zone fordispersing Na on solid finely divided carrier reaction product of aprevious cycle, a separate reaction zone for reacting Na and TiCl toform metallic Ti, a recycle of carrier reaction product thru said zonesin the order named, and separation from the circuit of reaction productformed during a cycle, the steps comprising providing a recycle carrierconsisting of reaction product of a previous cycle and containingmetallic Ti and NaCl, introducing said carrier into said dispersionzone, feeding elemental Na in liquid form into said zone, the amount ofNa being not substantially in excess of 3.5% by weight of total fed Naand carrier, passing thru said dispersion zone said Na and said carrierwhile maintained at temperature not higher than about 200 C. but highenough to insure the absence of solid Na,

and While in the absence of TiCL; and while under con-' ditions ofresidence and vigorous agitation both sufficient to efiect dispersion ofsaid Na on said carrier, thereafter discharging the mass ofthus-dispersed elemental Na and carrier from said dispersing zone andintroducing said mass into said separate reaction zone, feeding intosaid reaction zone vaporous TiCL; in quantity less than thattheoretically needed to react with all the elemental Na. present,maintaining temperature in said reaction zone in the range of aboutISO-350 C., passing the reactants thru said reaction zone while in theabsence of sodium from source other than said dispersing zone and whileunder conditions of residence and vigorous agitation both sufficient toeffect formation of a reaction mass comprising metallic Ti, NaCl andelemental Na, discharging said reaction mass from the reaction zone,separating from said mass reaction product in amount correspondingsubstantially to cyclic make, and recycling substantially the balance ofsaid mass to the dispersion zone, the entire foregoing operation beingcarried out in an inert atmosphere.

6. The process of claim 5 in which the TiCl Na reaction is effected inthe presence of at least 15% by weight of sodium in excess of thattheoretically needed to reduce all of the TiCL, fed to metallic Ti.

7. The process of claim 5 in which the solid carrier reaction productcontains suflicient sodium so that, in conjunction with fed sodium, theTiCl Na reaction is effected in the presence of about 15200% by Weightof sodium in excess of that theoretically needed to reduceall of theTiCl fed to metallic Ti.

8. The process of claim 5 in which the dispersed elemental sodium andcarrier material thereof are discharged into the reaction than C., andreaction zone temperature is maintained in the range of about 300 C.

9. The process of claim 5 in which the solid carrier reaction productcontains about 0.2'1.5% by weight of stoichiometric excess Na, therelative amounts of Na and' TiCL; charged are regulated to provide an Nafeed of at least about a stoichiometric quantity of Na on the basis offed TiCl and the amount of carrier charged into the dispersion zone isregulated so as to provide in the reaction zone a weight ratio ofcarrier to total weight of fed TiCl plus an approximately stoichiometricequivalent of fed Na substantially in the range of 60:1 to 25:1.

10. In a substantially continuous multi-stage cyclic process for makingmetallic Ti involving a circuit comprising a dispersing zone fordispersing carrier into said dispersion zone, feeding elemental Na" zoneat temperature not less' Na on solid finely divided carrier reactionproduct of a previous; cycle, a separate reaction zone for reacting Naandin liquid form into said zone and dispersing the fed Na on saidcarrier While at temperature high enough to insure absence of solidsodium but not higher than about 200 C. and While in the absence of TiCltransferring the thus dispersed Na and carrier thereof into saidreaction zone, feeding TiCl in vapor form into said reaction zone whilein the absence of sodium from source other than said dispersing zone andmaintained at temperature in the range of about ISO-350 C. to effectformation of metallic Ti and NaCl from fed reactants, regulatingrelative amounts of Na and TiCL, charged to provide a Na feed of about astoichiometric quantity of Na on the basis of fed TiCl regulating theamount of recycle charged into the dispersion zone so as to provide inthe reaction zone a weight ratio of recycle to total weight of fed T iClplus an approximately stoichiometric equivalent of fed Na substantiallyin the range of 60:1 to 25:1, discharging reaction mass from thereaction zone, separating from said mass reaction product in amountcorresponding approximately to cyclic make, and recycling substantiallythe balance of said mass to the dispersion zone, the entire foregoingoperation being carried out in an inert atmosphere.

11. The process of claim 10 in which the dispersed elemental sodium andcarrier thereof are discharged into the reaction zone at temperature notless than 125 C., and reaction zone temperature is maintained in therange of about 175-300 C.

12. The process of claim 10 in which the total amount of Na introducedinto the system is in excess of theoretical Na requirements to an extentapproximately corresponding with the amount of the bleed loss Nacontained in the cyclic make and cyclically discharged from the circuit.

13. The process of claim 10 in which sodium and carrier in thedispersion zone and solids in the reaction zone are maintained in theforms of vigorously mechanically agitated contiguously constituted bedsof substantially dry, free-flowing materials.

References Cited in the file of this patent UNITED STATES PATENTS2,343,780 Lewis Mar. 7, 1944 2,481,226 Krebs Sept. 6, 1949 2,618,549Glasser et a1 Nov. 18, 1952 2,618,550 Hampel et a1 Nov. 18, 19522,620,313 Odell Dec. 2, 1952 FOREIGN PATENTS 386,621 Great Britain Feb.16, 1933 694,921 Great Britain July 29, 1953 717,930 Great Britain Nov.3, 1954 1,069,706 France Feb. 17, 1954

2. IN A MULTI-STAGE PROCESS FOR MAKING METALLIC TATANIUM INVOLVING LOWTEMPERATURE REDUCTION OF TITANIUM TETRACHLORIDE WITH ELEMENTAL ALKALIMETAL, OF THE GROUP CONSISTNG OF SODIUM, POTASSIUM AND NAK ALLOY,DISPERSED THROUGHOUT A MANY TIMES GREATER WEIGHT BULK OF FINELY DIVIDEDSUBSTANTIALLY FREE-FLOWING SOLID CARRIER MATERIAL OF THE GROUPCONSISTING OF ALKALI METAL CHLORIDE, METALLIC TITANIUM AND MIXTURESTHEREOF, THE IMPROVEMENT COMPRISING DISPERSING ELEMENTAL ALKALI METAL INLIQUID FORM ON THE CARRIER MATERIAL IN A DISPERSING ZONE WHICL HELD ATTEMPERATURE SUCH AS TO MAINTAIN ALKALI METAL IN LIQUID FORM AND HIGHENOUGH TO INSURE ABSENCE OF SOLID ALKALI METAL AND WHILE MAINTAINING THEABSENCE OF TITANIUM TETRACHLORIDE, THEREAFTER TRANSFERRING THE THUSDISPERSED ELEMENTAL ALKALI METAL AND CARRIER MATERIAL THEREOF FROM SAIDDISPERSING ZONE INTO A SEPARATE REACTION ZONE WHILE IN THE ABSENCE OFALKALI METAL FROM SOURCE OTHER THAN SAID DISPERSING ZONE AND WHILEFEEDING TITANIUM TETRACHLORIDE IN VAPOR FORM INTO SAID REACTION ZONE ANDWHILE MAINTAINING THEREIN MODERATELY ELEVATED TEMPERATURE SUBSTANTIALLYBELOW THE FUSION POINT OF THE CHLORIDE OF THE REDUCING ALKALI METAL BUTHIGH ENOUGH TO EFFECT PRODUCTION OF A REACTION MASS COMPRISING METALLICTITANIUM AND ALKALI METAL CHLORIDE, AND DISCHARGING SAID REACTION MASSFROM SAID REACTION ZONE, THE ENTIRE FOREGOING OPERATION BEING CARRIEDOUT IN AN INERT ATMOSPHERE.